Pneumatic propulsion means



No. 624,271. Patented May 2, I899.

.l. C. WALKER.

PNEUMATIC PROPULSION MEANS.

(Application filed May 10, 1598.)

(No Model.)

/N VENTOI? WITNESSES.

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UNITED STATES PATENT OFFICE.

JAMES C. YVALKER, OF WACO, TEXAS.

PNEUMATIC PROPULSION MEANS.

SPECIFICATIONforming part of Letters Patent N 0. 624,271, dated May 2,1899. Application filed May 10, 1898. Serial Nox 680,306. (No model.)

To all whom it may concern;

Be it known that 1, JAMES C. WALKER, residing at Waco, in the county ofMcLennan and State of Texas, have invented a new and Improved PneumaticPropulsion Means, of which the following is a specification.

This invention has for its purpose to provide for a direct and efficientapplication of currents of air to aid the propulsion of ships or boatsand in the adaptation of the form of the ship or boat and its propellingmeans to this particular mode of propulsion.

This invention comprehends generally 'a construction of the hull of thevessel whereby air is capable of being so distributed as to produce acushion on which the vessel is to float as much as possible instead ofdirectly on the water and means provided whereby to reduce cavitation onthe rear of the boat and of the propeller to a minimum.

In its subordinate features my invention embodies certain details ofconstruction and novel combination of parts, as will hereinafter befirst described in detail, and then pointed out in the appended claims,reference being had to the accompanying drawings, in which Figure 1 is adiagrammatic longitudinal section illustrating a boat or ships hull anda propeller embodying the general features of myinvention. Fig. 2 is adiagrammatic front view of the parts shown in Fig. 1. Fig. 3 is atransverse section of the same on the line 3 3 of Fig. 1. Fig. 4 is arear end view.

One of the essential features of this invention is to overcome so far aspossible friction and the formation of cavities or vacuumspaces back ofthe propeller-blades, which have a retarding action on the propulsion ofthe vessel. This formation I seek to overcome by the means illustratedin a general way in the accompanying drawings, it being understood,however, that I do not confine my invention to the particularconstruction of the parts shown, as they may be readily modified withoutdeparting from the scope of the claims hereinafter set out.

Referring to the drawings, in which like letters indicate like parts inall the figures, A indicates the boat body or hull, which may be in itsgeneral construction of any well-known form. At a suitable point withinthe hull is mounted ablowerB or other means for collecting air anddischarging it under great pressure either in a continuous orintermittent blast. This blower connects by a pipe B with what I termthe main air-tube D, located in the bow of the boat and having adischarge end of grad ually-decreasin g area,which opens through ajet-outlet a into the main air-chamber E which extends the full lengthof the keel and terminates just below the water-line, while the rear endterminates at or near the propeller-line.

The channel or duct ll. is to be strongly made of metal and preferablyof semicircular form, as shown in Figs. 2, 3, and 4, the side members Ethereof being of dimensions proportionate to the sides of the boat orship to which they are attached.

a a indicate channels or ducts similar to the channels E", but of asomewhat smaller area, such channels a at extending from the bowto thestern and fixedly secured to the side of the hull at a point below thewaterline, each of such channels a being connected with theair-conductor pipe D by laterals a, which at their exit from the insideof the hull to the channels a make a sudden bend and extend a shortdistance into the air-channels, as indicated at a such ends projectingrearwardly, so that the water passing them serves to suck the air alongthe channel to the rear ends.

The air forced into the several side chan-' nels is held by theouter.rims of such channels, as clearly indicated in Fig. 2, and at thestern all the air-channels a, aturn inward toward the propeller-line, asshown in Fig. 4, so as to lead the air over and around the stern, andthereby prevent cavitation back of i the same by reason of the moving ofthe stern forward through the water. charging air just to the rear ofthe stern formation of cavities, the amount of which is proportionate tothe speed of the boat, is not alone avoided, but the friction along andbeneath the ship is also materially so reduced that the speed of theboat is greatly increased thereby.

By arranginga number of air ducts or channels as shown cushion portionsfor the hull will be maintained at all times, even should the tossing orrolling of the boat cause one By thus disor more of the side ducts orchannels to rise above the water-line, it being understood that theemersion of such exposed channels admits of their being quickly filledfrom the constant current action of the blower B, and to facilitate thisaction the side channels are graduated and a little higher at the sternthan at the bow.

The blower B, which can be placed at any convenient point inside thehull, may be run by a suitable motor or by gearing with thepropeller-operating mechanism.

On sail-boats the air-pipe D is extende and terminates in a concentratoror collector O, which when turned to the wind will generally supplysufficient air for the purposes contemplated. In steam vessels thecollector O is dispensed with.

In the practical application of my improved form of ships hull the sameis to be used with a peculiar construction of propeller, of which one ormore may be used, and which is made with the View of also serving as anair-duct, adapted to fill any cavity or vacuum which might be createddirectly to the rear of the propeller, which action is augmented by theair force in the side channels and serv'esto positively overcome thecreation of a vacuum For this purpose said propeller'serves as a meansfor discharging air at the point stated, 0

which has a necessary correlation with the peculiar form of ships hull.The details of construction of such propeller, however, form thesubject-matter of another application filed by me on the 10th day ofJanuary, 1898, Se- 5 rial No. 701,772, and such details ofconstrucdischarging air through the stern to a point in line with thepropeller, substantially as described.

2. As an improvement in ship propulsion; a ships hull having akeel-channel extending from the forward to the rear end and ter-"minating in an upturned tapering discharge; means for discharging anair-jet directly rearward through the stern; said hull having a seriesof 'side external channels, having their discharge ends extendingrearward toward the center of the stern; an air-co mpressorhaving a maindischarge-opening into the keelchannel, and a series of lateralsextending into the side channels and having theirends projectingrearward in such channels, all substantially as shown and described.

JAMES C. WALKER.

Witnesses:

G. I. BATTLE, JNo. T. BATTLE.

